Nearly 80% of Macs will be able to run OS X Yosemite

iPhone 4 won't be able to handle iOS 8

OS X Yosemite will run on about eight out of every ten Macs, a boon for customers who want to upgrade this fall, but also another proof point that "good enough" has contributed to the personal computer business's stagnation.

Keeping with tradition, Apple dumped support for iOS 8 on the iPhone 4, leaving the four-year-old flagship stuck on iOS 7.

OS X 10.10, aka Yosemite -- named after the California national park -- will support the same Macs as 2012's Mountain Lion and 2013's Mavericks, according to accounts of the Yosemite preview's system requirements.

Computerworld confirmed the supported-Macs accounts with developers, who asked not to be named because they weren't authorized to disclose information about the pre-release software.

Yosemite's list was identical to Mavericks' of last year, which had been nearly the same as Mountain Lion's the year before.

OS X 10.10 will run on iMacs from the mid-2007 model on; on 13-in. MacBooks from late 2008 (aluminum case) and early 2009 (plastic case) forward; MacBook Pro notebooks from mid-2009 and later (13-in.) and late-2007 and after (15-in., discontinued 17-in.) and on; MacBook Air ultra-light laptops from late 2008 and later; Mac Mini desktops from early 2009 and after; and the much beefier Mac Pro desktops from early 2008 and forward.

Mac owners can determine the age of their machine by selecting "About This Mac" from the Apple menu at the far left of the menu bar, then choosing "More Info..." from the ensuing window. The Mac's age will appear under the name of the model, as something like "Retina, 13-inch, Late 2012" for a MacBook Pro laptop.

Until 2012's Mountain Lion, Apple regularly trimmed its supported hardware list, dumping what it considered old as it added features to the operating system that either would not run on the aging machines, or would run poorly.

But like Microsoft -- whose Windows 8 and 8.1 runs on the same hardware as the five-year-old Windows 7, which in turn runs on the same hardware as 2007's Windows Vista -- Apple has lately acknowledged that older Macs are good enough for its upgrades.

According to Internet metrics company Net Applications, 69% of all Macs that went online in May ran Mountain Lion or Mavericks, and will definitely handle Yosemite. A portion of the systems still on 2011's Lion will also be able to run OS X 10.10.

If Mountain Lion and Mavericks sustain their 90-day average losses and gains through September, the month before Yosemite is expected to launch, the two editions will be on 78% of all Macs as Yosemite reaches its release date.

By September, the month before OS X Yosemite releases, about eight of every 10 Macs will be running Mavericks or Mountain Lion, and thus eligible for the upgrade to 10.10. (Data: Net Applications.)